[Axel]

Based on the 1/4 mi times and trap speeds posted by GM:
SKY: 15.7 at 89mph Redline: 13.9 at 100 mph

http://media.gm.com/us/gm/en/news/events/autoshows/06ny/brands/saturn/06_NY_Sat_SkyRL_Spec.htm

The calculated 2.4L Sky and RL horsepower are as follows:
Formula is HP= weight * ( speed/228.4) cubed
Older formulas u may have seen used 234 but that was before NHRA changed
their way trap speeds were measured in 1989.

For regular SKY, the hp calculates to 184 hp

For Redline, the HP calculates to 266 hp

Usually MPH * ET=about 1380 to 1400 so the GM 1/4 mile time is
right inline with its trap speed. Thus HP is pretty close.

 

[tvieira24]

I'm assuming these calculations are to the crank?

 

[Jordan]

Definately at the crank.

 

[brentil]

Those values appear to be within a % varience, so it seems good.

 

[Freakazoid]

I'd be sorta surprised if it was only 260 at the crank, with how badly they underrated the IRL. Assuming that, I can DEFINITELY see the car running solid mid 13's with a decent driver.

 

[hmong337]

I'd like to see some dynojet numbers... hp at the crank means nothing! wheel horsepower is where it's at.

 

[MEGAS]

given the fact that it's a rw drive with LSD my estimate is about 230-235 RWHP.

EDIT...sorry i meant to write 220-225 which is about 15% drive losses.

if you look at an s2k it's about 15%...240 crank 205 flywheel.

 

[hmong337]

given the fact that it's a rw drive with LSD my estimate is about 230-235 RWHP.

Well... a rule of thumb is usually 20% drivetrain loss with 80% of the power getting to the ground.

With that being said, 260*0.8 = 208 wheel HP which isn't bad. It's a good start for being stock.

 

[Freakazoid]

Well... a rule of thumb is usually 20% drivetrain loss with 80% of the power getting to the ground.

With that being said, 260*0.8 = 208 wheel HP which isn't bad. It's a good start for being stock.

I would still expect some serious underrating all and all.... and I thought 15% drivetrain was expected/standard for most carS? If the Sky RL only has 200-210 whp that would be rather pathetic sorry, it should definitely have more hp than the IRL counterpart....

 

[usmc]

Well... a rule of thumb is usually 20% drivetrain loss with 80% of the power getting to the ground.

With that being said, 260*0.8 = 208 wheel HP which isn't bad. It's a good start for being stock.

correct... the solstice has seen abour22-24% loss from flywheel to wheels.

you guys should check out the sol forum for more info. They've had their cars longer and mucho info with dyno results over there. (for the base sol, not gxp yet)

 

[hmong337]

I would still expect some serious underrating all and all.... and I thought 15% drivetrain was expected/standard for most carS? If the Sky RL only has 200-210 whp that would be rather pathetic sorry, it should definitely have more hp than the IRL counterpart....

hmmm... I wouldn't be too sure about that. Manufacturers nowadays actually "over-rate" their horsepower figures to make their vehicles sound better. A prime example of this is the Mazda RX-8. That car is like half the power of what they claim.

It's only when manufacturers have to stay within a certain horsepower range that they underrate their figures in order to sell their cars. An example of this is the Nissan Skyline R34. Nissan rated the R34 at 280hp but in reality it's pushing more like 320hp+

So in retrospect, I HIGHLY doubt the Sky redline will be making more than 220hp to the wheels. And I'm sure the 260hp flywheel number has been inflated somewhat.

best regards,

Hmong337

 

[brentil]

10~15% is rule of thumb for FWD and 15~20% is rule of thumb for RWD. It's not always true so I personally don't like using those values for anything besides guessing. Recently with the shift to the new HP rating standards GM was actually one of the few companies where several of it's engines went up in HP unlike most of your Asian cars which went down in values. The underated debate most times stems back to the LSJ in the Cobalt SS since GM underrated it's values a good bit.

 

[usmc]

10~15% is rule of thumb for FWD and 15~20% is rule of thumb for RWD. It's not always true so I personally don't like using those values for anything besides guessing. Recently with the shift to the new HP rating standards GM was actually one of the few companies where several of it's engines went up in HP unlike most of your Asian cars which went down in values. The underated debate most times stems back to the LSJ in the Cobalt SS since GM underrated it's values a good bit.

20% is a good number to guess with...

and in this case, was very close.... the sol is about 22% loss, so figure sky to be the same.

 

[Freakazoid]

10~15% is rule of thumb for FWD and 15~20% is rule of thumb for RWD. It's not always true so I personally don't like using those values for anything besides guessing. Recently with the shift to the new HP rating standards GM was actually one of the few companies where several of it's engines went up in HP unlike most of your Asian cars which went down in values. The underated debate most times stems back to the LSJ in the Cobalt SS since GM underrated it's values a good bit.

yea that's exactly what I'm stemming my debate from I'm very familiar with the IRL (and the SS to a degree), and those cars were underrated quite noticeably. The fact that the SS was underrated and still not fixed makes me wonder if it it's a deliberate move on GM's part. If it truly ends up losing that much to the wheels though I'll be a little saddened 200-210 whp will not be remotely enough for a car that's probably goin to cost 30k+. My 2 cents I just hope it doesnt' lose that much or even better it IS 260 at the wheels (pushing it MAJOR league for a 2.0L engine, but I can dream!)

 

[carlintexas]

Info from the other side

The Hahn stage two turbo takes the 2.4 base engine to 242hp at the wheel and one of the only units out there did the 1/4 in 13.6 @ 103mph.
:cheers:

 

[usmc]

The Hahn stage two turbo takes the 2.4 base engine to 242hp at the wheel and one of the only units out there did the 1/4 in 13.6 @ 103mph.
:cheers:

YAAAA baby!!!!!!!!!!

now I just need 4k to pay for it.

 

[hmong337]

The Hahn stage two turbo takes the 2.4 base engine to 242hp at the wheel and one of the only units out there did the 1/4 in 13.6 @ 103mph.
:cheers:

With your statement... I had to do some research. I never knew there was already a turbo system developed...

[Information removed by moderation staff. Hahn is not a Supporting Vendor at this site yet. Therefore linking to their site and posting images from their site is not permited per the forum policies.]

 

[usmc]

There are a couple of companies making turbos for the sky. Hahn is just one.

 

[brentil]

There are a couple of companies making turbos for the sky. Hahn is just one.

One of our Supporters here, www.clearimageautomotive.com is working on a kit now.

 

[Jack B]

A little insight from the experience of a 100 plus dyno pulls. The losses thru the drive train are typically in the range of 12-15% for a new drive train and a rear wheel drive car with a manual transmission. With a solid axle they would be on the lower side, with IRS and half-shafts they would be on the higher side. As the car ages the losses go up, in addition, as the rear axle ratio gets numerically higher the losses also go up. In summary, the GXP/Sky probably have losses in the 13-14% range.

I ordered the GXP this week and hope to put it in the garage with the viper.